Final answer:
A glide reflection is a combination of a translation and a reflection. The glide reflection maps DEF onto D’E’F’ and the line of reflection is parallel to the y-axis with a translation distance of 1 unit.
Step-by-step explanation:
A glide reflection is a combination of a translation and a reflection. It can be represented as the composition of two transformations: first a reflection over a line, and then a translation along that line. The line of reflection is the axis of glide reflection and the amount of translation is the distance of glide reflection.
In this case, the glide reflection maps DEF onto D’E’F’, and the notation Ry=1 indicates that the line of reflection is parallel to the y-axis and the translation distance is 1 unit. So, in terms of the coordinates of the points, the transformation is (x, y) → (x, -y) → (x+1, -y).
Since the transformation Ry=1 is given, we can rewrite the given points in the new coordinates of D’E’F’. If the original coordinates of D, E, F are (x, y), the transformed coordinates will be (x, -y), and then (x+1, -y). So we have D’ = (x, -y), E’ = (y, -x), and F’ = (y+1, -x).